Active control of mid-wavelength infrared non-linearity in silicon photonic crystal slab

Natural materials' inherently weak nonlinear response demands the design of artificial substitutes to avoid optically large samples and complex phase-matching techniques. Silicon photonic crystals are promising artificial materials for this quest. Their nonlinear properties can be modulated optically, paving the way for applications ranging from ultrafast information processing to quantum technologies. A two-dimensional 15-μm-thick silicon photonic structure, comprising a hexagonal array of air holes traversing the slab's thickness, has been designed to support a guided resonance for the light with a wavelength of 4-μm. At the resonance conditions, a transverse mode of the light is strongly confined between the holes in the "veins" of the silicon component. Owing to the confinement, the structure exhibits a ratio of nonlinear to linear absorption coefficients threefold higher than the uniform silicon slab of the same thickness. A customised time-resolved Z-scan method with provisions to accommodate ultrafast pump-probe measurements was used to investigate and quantify the non-linear response. We show that optically pumping free charge carriers into the structure decouples the incoming light from the resonance and reduces the non-linear response. The time-resolved measurements suggest that the decoupling is a relatively long-lived effect on the scale comparable to the non-radiative recombination in the bulk material. Moreover, we demonstrate that the excited free carriers are not the source of the nonlinearity, as this property is determined by the structure design.

Research participants may not recall their participation but have a better understanding of alternative management options than patients in routine care

BACKGROUND

Patient understanding of care interventions, of the clinical uncertainty, and of their participation in clinical research is often poor. We hypothesized that compared to routine care, patients would better understand the prevailing uncertainty when they participated in research.

METHODS

A questionnaire was administered to patients at the time they attended a follow-up neurovascular clinic 4 to 52 weeks after a care episode where they did or did not participate in a clinical trial. Patients were not reminded whether they had previously participated in a clinical trial. Questions concerned their understanding of the risks/benefits of interventions, the availability of alternative options, whether their personal opinion was taken into consideration, the reason for the final decision, their confidence at having received the best management, and whether they had been research participants.

RESULTS

Between June 2019 and June 2020, 167 patients were recruited; 71 had truly been research participants, while 96 had not. A greater proportion of research patients were aware of the existence of management alternatives (65% versus 44%; P=0.008). Patients of both groups believed their personal opinion counted in the final decision (76% versus 70%), and patients were equally confident that they had received the best management (94%). Research patients believed they had participated in research 46% of the time, compared to 12% of routine care patients (P=0.003).

CONCLUSION

Many patients do not recall that they participated in a clinical trial, but they have a better understanding of the clinical uncertainty and of the availability of alternative management options.

Predicting Molecular Subtype and Survival of Rhabdomyosarcoma Patients Using Deep Learning of H&E Images: A Report from the Children's Oncology Group

PURPOSE

Rhabdomyosarcoma (RMS) is an aggressive soft-tissue sarcoma, which primarily occurs in children and young adults. We previously reported specific genomic alterations in RMS, which strongly correlated with survival; however, predicting these mutations or high-risk disease at diagnosis remains a significant challenge. In this study, we utilized convolutional neural networks (CNN) to learn histologic features associated with driver mutations and outcome using hematoxylin and eosin (H&E) images of RMS.

EXPERIMENTAL DESIGN

Digital whole slide H&E images were collected from clinically annotated diagnostic tumor samples from 321 patients with RMS enrolled in Children's Oncology Group (COG) trials (1998-2017). Patches were extracted and fed into deep learning CNNs to learn features associated with mutations and relative event-free survival risk. The performance of the trained models was evaluated against independent test sample data (n = 136) or holdout test data.

RESULTS

The trained CNN could accurately classify alveolar RMS, a high-risk subtype associated with PAX3/7-FOXO1 fusion genes, with an ROC of 0.85 on an independent test dataset. CNN models trained on mutationally-annotated samples identified tumors with RAS pathway with a ROC of 0.67, and high-risk mutations in MYOD1 or TP53 with a ROC of 0.97 and 0.63, respectively. Remarkably, CNN models were superior in predicting event-free and overall survival compared with current molecular-clinical risk stratification.

CONCLUSIONS

This study demonstrates that high-risk features, including those associated with certain mutations, can be readily identified at diagnosis using deep learning. CNNs are a powerful tool for diagnostic and prognostic prediction of rhabdomyosarcoma, which will be tested in prospective COG clinical trials.

Understanding the research-care demarcation and why it must be revised

BACKGROUND

A clean-cut separation between research and care was artificially created at the time of the Belmont report more than 40 years ago. The demarcation was initially controversial but eventually was implemented for political reasons. We examine why it must be revised.

METHODS

We review historical research scandals as well as the theoretical basis for the Belmont demarcation. We then discuss consequences on medical practice and propose an alternative.

DISCUSSION

Most research scandals involved abusing human beings supposedly for the sake of science. Belmont commissioners were aware the research/care problem was double-headed. While research subjects should be protected from abuse in the research context, patients need to be protected from unvalidated medical and surgical interventions in the care context. For political reasons the Commission recommended the regulation of research but to leave medical practice untouched. Thus the Commission had to distinguish research from care. The notion of 'generalizable knowledge' was introduced to define and regulate research, but the inadvertent result was that by trying to protect research subjects, the regulation has not only failed to protect all other patients, but also encouraged the widespread practice of unvalidated interventions within the care context. The notion of validated care should be re-introduced into a proper analysis of the care-research demarcation, for care research is an integral ingredient of a good medical practice.

CONCLUSION

The research-care demarcation should be revised to leave room for the validated/unvalidated care distinction. Care research, essential to guide medical practice, should be facilitated at all levels.

Structural variant analysis of a cancer reference cell line sample using multiple sequencing technologies

BACKGROUND

The cancer genome is commonly altered with thousands of structural rearrangements including insertions, deletions, translocation, inversions, duplications, and copy number variations. Thus, structural variant (SV) characterization plays a paramount role in cancer target identification, oncology diagnostics, and personalized medicine. As part of the SEQC2 Consortium effort, the present study established and evaluated a consensus SV call set using a breast cancer reference cell line and matched normal control derived from the same donor, which were used in our companion benchmarking studies as reference samples.

RESULTS

We systematically investigated somatic SVs in the reference cancer cell line by comparing to a matched normal cell line using multiple NGS platforms including Illumina short-read, 10X Genomics linked reads, PacBio long reads, Oxford Nanopore long reads, and high-throughput chromosome conformation capture (Hi-C). We established a consensus SV call set of a total of 1788 SVs including 717 deletions, 230 duplications, 551 insertions, 133 inversions, 146 translocations, and 11 breakends for the reference cancer cell line. To independently evaluate and cross-validate the accuracy of our consensus SV call set, we used orthogonal methods including PCR-based validation, Affymetrix arrays, Bionano optical mapping, and identification of fusion genes detected from RNA-seq. We evaluated the strengths and weaknesses of each NGS technology for SV determination, and our findings provide an actionable guide to improve cancer genome SV detection sensitivity and accuracy.

CONCLUSIONS

A high-confidence consensus SV call set was established for the reference cancer cell line. A large subset of the variants identified was validated by multiple orthogonal methods.

The Adapted Firesetting Assessment Scale: reliability and validity

BACKGROUND

The Adapted Firesetting Assessment Scale was developed for use with adults with developmental disabilities targeting fire-related factors thought to be associated with deliberate firesetting behaviour (i.e. attitudes towards fire, fire interest, fire normalisation, identification with fire and fire safety awareness). However, the psychometric properties of the scale are yet to be evaluated.

METHOD

The reliability, validity, comprehensibility, relevance and comprehensiveness of the Adapted Firesetting Assessment Scale were evaluated. Fifty-nine adults with developmental disabilities, some of whom had a history of firesetting, completed the Adapted Firesetting Assessment Scale on two occasions. Feedback about the questionnaire was sought from both participants and professionals.

RESULTS

The AFAS has acceptable internal consistency and excellent test-retest reliability. The attitudes towards fire, fire normalisation, poor fire safety subscales and total scores discriminated firesetters from non-firesetters. Content analysis of feedback indicated items of the AFAS were understood, relevant, accessible and comprehensible.

CONCLUSION

A larger study is needed to examine the factor structure of the AFAS.

Abstract 466: Predicting survival of rhabdomyosarcoma patients based on deep learning of H&E images

Background: Rhabdomyosarcoma (RMS) is an aggressive soft tissue tumor in children and young adults, accounting for 350-400 new cases annually in the US. Diagnosis of RMS is defined by the expression of genes related to skeletal muscle differentiation and can be further subclassified based on histological patterns (embryonal, ERMS; alveolar, ARMS; spindle/sclerosing, SSRMS). Genetic studies have found that the presence of a PAX fusion gene (FP-RMS), which is present in many ARMS tumors, correlates with poor outcome. Subsequent studies have identified additional genetic alterations (ex. TP53 or MYOD1 mutations) which also display distinct histological features and are associated with poor outcome. As a result, there is a growing need to identify these mutations to improve risk stratification. The goal of this study is to develop and test deep learning algorithms from diagnostic H&E images of RMS tumors which can aid in the diagnosis, mutation prediction and risk stratification for RMS patients.

Methods: De-identified RMS patient samples were collected from tissue banking studies from Children’s Oncology Group (n=275), University Hospital Zurich (n=250) and Memorial Sloan Kettering (n=10). H&E stains on whole slides or TMAs were digitally scanned and used for analysis. Clinical information including clinical risk group, event-free survival, and genomic findings were used as available for training and testing. Convolutional neural networks (CNN) using EfficientNet were trained using K-fold cross validation to classify tumor histology, mutation probability, and risk stratification and tested against randomly selected samples or independent datasets when available.

Results: The developed AI algorithm was able to classify tissue as ARMS (FP-RMS), ERMS (FN-RMS), stroma and necrosis with an average weighted intersect-over-union of 0.74 when compared to an expert pathologist annotation. A second deep learning algorithm developed specifically for distinguishing FP-RMS from FN-RMS displayed excellent sensitivity (FP-RMS=0.88) and specificity (FP-RMS=0.86) when tested against an independent RMS TMA dataset. Algorithms were also trained to predict mutations in MYOD1, RAS pathway genes, and TP53 and displayed good performance with ROC values of 0.96, 0.68, and 0.64, respectively. Lastly, we developed an algorithm to provide a Cox proportional hazard prediction based on H&E images. The resulting algorithm was capable of predicting EFS with similar accuracy as current clinical risk group assessment with improved ability to distinguish intermediate and high risk patients.

Conclusions: Deep learning with convolutional neural networks provides pathologist-independent classification of RMS patients from simple H&E images. These AI algorithms can provide probabilities of prognostically relevant genetic alterations and survival which will ultimately contribute to better risk stratification of RMS patients.

Citation Format: David Milewski, Hyun Jung, G. Thomas Brown, Yanling Liu, Jack Collins, Marc Ladanyi, Erin Rudzinski, Javed Khan. Predicting survival of rhabdomyosarcoma patients based on deep learning of H&E images [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 466.

Taming non-radiative recombination in Si nanocrystals interlinked in a porous network

A range of the distinctive physical properties, comprising high surface-to-volume ratio, possibility to achieve mechanical and chemical stability after a tailored treatment, controlled quantum confinement and the room-temperature photoluminescence, combined with mass production capabilities offer porous silicon unmatched capabilities required for the development of electro-optical devices. Yet, the mechanism of the charge carrier dynamics remains poorly controlled and understood. In particular, non-radiative recombination, often the main process of the excited carrier's decay, has not been adequately comprehended to this day. Here we show, that the recombination mechanism critically depends on the composition of surface passivation. That is, hydrogen passivated material exhibits Shockley-Read-Hall type of decay, while for oxidised surfaces, it proceeds by two orders of magnitude faster and exclusively through the Auger process. Moreover, it is possible to control the source of recombination in the same sample by applying a cyclic sequence of hydrogenation-oxidation-hydrogenation processes, and, consequently switching on-demand between Shockley-Read-Hall and Auger recombinations. Remarkably, irregardless of the recombination mechanism, the rate constant scales inversely with the average volume of individual silicon nanocrystals contained in the material. Thus, the type of the non-radiative recombination is established by the composition of the passivation, while its rate depends on the degree of the charge carriers' quantum confinement.

A Systematic Review of Autistic People and the Criminal Justice System: An Update of King and Murphy (2014)

The purpose of this paper was to determine whether recommendations made by King & Murphy (Journal of Autism and Developmental Disorders 44:2717-2733, 2014) in their review of the evidence on autistic people in contact with the criminal justice system (CJS) have been addressed. Research published since 2013 was systematically examined and synthesised. The quality of 47 papers was assessed using the Mixed Methods Appraisal Tool. Findings suggest a limited amount of good quality research has been conducted that has focused on improving our understanding of autistic people in contact with the CJS since 2013. Methodological limitations make direct comparisons between autistic and non-autistic offenders difficult. Autistic people commit a range of crimes and appear to have unique characteristics that warrant further exploration (i.e., vulnerabilities, motivations for offending).

183 A Systematic Review of Sample Size Calculations in High-Profile Surgical Trials That Use Patient-Reported Outcome Measures

Background

Patient reported outcome measures (PROMs) are increasingly recognised as a measure of treatment efficacy in randomised controlled trials (RCTs). It can be difficult to determine meaningful target differences in PROM scores for sample size calculations and this can risk over-recruitment and/or erroneous trial conclusions. The Difference ELicitation in TriAls (DELTA2) statement sets recommendations for sample size calculations in RCTs including target difference determination. We aimed to evaluate sample size calculations from high-profile surgical RCTs that used PROMs as their primary outcome, against DELTA2 standards, with a focus on target differences.

Method

Pubmed was systematically searched for surgical RCTs published in the five highest ranking journals, by Thomson Reuters impact factor, for medicine and surgery. Studies were included if surgery was the intervention and/or comparator arm, and a PROM was the primary outcome. Surgery was defined as using instrumentation to change macro-anatomy with the aim of improving health. Data were extracted with a piloted data collection sheet that included the DELTA2 reporting recommendations.

Results

Most target differences used in sample size calculations were determined with suboptimal techniques and target difference justification was overall poor. In this sample, £28 million of UK public research spending supported trials with poor target difference justification.

Conclusions

In this sample of trials, sample size calculations were generally not reported to DELTA2 standards. There was frequent use of sub-optimal methods to determine the target difference. This risks over-recruitment and/or erroneous trial conclusions. Clinicians should be aware of these potential pitfalls when interpreting published trials.

Real-time Detection of Patient Head Position and Cephalometric Landmarks from Neuro-Interventional Procedure Images Using Machine Learning for Patient Eye-Lens Dose Prediction

A deep learning (DL) model has been developed to estimate patient-lens dose in real-time for given exposure and geometric conditions during fluoroscopically-guided neuro-interventional procedures. Parameters input into the DL model for dose prediction include the patient head shift from isocenter and cephalometric landmark locations as a surrogate for head size. Machine learning (ML) models were investigated to automatically detect these parameters from the in-procedure fluoroscopic image. Fluoroscopic images of a Kyoto Kagaku anthropomorphic head phantom were taken at various known X (transverse) and Y (longitudinal) shifts, as well as different magnification modes, to create an image database. For each image, anatomical landmark coordinate locations were obtained manually using ImageJ and are used as ground-truth labels for training. This database was then used to train the two separate ML models. One ML model predicts the patient head shift in both the X and Y directions and the other model predicts the coordinates of the anatomical landmarks. From the coordinates, the distance between these anatomical landmarks is calculated, and input into the DL dose-prediction model. Model performance was evaluated using mean absolute error (MAE) and mean absolute percentage error (MAPE) for the head-shift and landmark-coordinate models, respectively. The goal is to implement these two separate models into the Dose Tracking System (DTS) developed by our group. This would allow the DTS to automatically detect the patient head size and position for eye-lens dose prediction and eliminate the need for manual input by the clinical staff.

141 New Guidelines to Reduce Unnecessary Blood Tests, Delayed Discharge and Costs Following Robot Assisted Radical Prostatectomy

Objectives

Routine postoperative blood tests (POBT) following robot assisted radical prostatectomy (RARP) are used to evaluate the impact of surgery on pre-existing co-morbidities and to detect early complications. This practice dates back to an era of open surgery, when blood loss and complication rates were higher. We propose new guidelines to improve the specificity of POBT.

Method

The cases of 1040 consecutive patients who underwent a primary or salvage RARP at two large tertiary urology centres in the United Kingdom were retrospectively reviewed to form new guidelines. The new guidelines were prospectively validated in a sample of 300 patients.

Results

Derivation Dataset: 3% and 5% had intra- and post-operative Clavien-Dindo complications, respectively. 15% had clinical concerns postoperatively. 0.9% required perioperative transfusion. 78% had routine blood tests without clinical concerns, none of whom developed a complication. 98% of complications were suspected by clinical judgement. 6% of patients had a discharge delay of ≥ 1 day due to delayed or incomplete blood tests. Validation Dataset: No significant difference existed in complication, clinical concern or transfusion rates between the derivation and validation datasets. Number of POBT requested reduced by 73% (p < 0.001). The new guidelines improved POBT sensitivity for complications from 98% to 100% and specificity from 0% to 74%. Discharge delays reduced from 6% to 0% (p = 0.008). Cost savings were £178 per patient.

Conclusions

Postoperative complications and transfusion following RARP are rare. Routine POBT without clinical indication are unnecessary and inefficient. A guideline-based approach to POBT can reduce costs and optimise discharge without compromising patient safety or care.

1420 ViRtual prOficiency Based prOgression for Robotic Training (VROBOT): A Prospective Cohort Study Protocol

Introduction

Robotic surgery is an evolving field that requires specialist training. Historically, robotic surgery training has lacked standardisation. Recently, training centres have introduced proficiency-based modules and curriculums to certify and progress the skills of novice robotic surgeons. However, training tends to be self-directed and non-interactive. Limited interactive teaching does exist but can be inaccessible and expensive. We aim to validate the effectiveness of the current Fundamentals of Robotic Surgery (FRS) training curriculum with the addition of interactive virtual classroom teaching.

Method

16 novice surgical trainees will be assigned to two training groups. The interventions will be implemented following a one-week robotic skills induction. Both groups will receive access to the FRS curriculum for one week. The intervention group will additionally receive virtual classroom robotic skills training. The primary outcome will be the objective performance scores after training using a synthetic model based on task errors, time taken and contact pressure. In week 3, each group will receive the alternate intervention and objective performance scores will be measured to determine the trajectory of scores.

Results

Significant objective performance improvement following the intervention will be indicative of intervention quality.

Conclusions

This will be the first feasibility study evaluating the efficacy of interactive virtual robotic surgery training. It will determine the effect size of virtual classroom training on the development of basic robotic surgical skills in addition to the proficiency-based FRS curriculum. The findings will assist the development and implementation of further resource-efficient virtual robotic surgical skills training programs.

Complications of combination intranasal corticosteroids and anti-retroviral therapy

BACKGROUND

Intranasal corticosteroids are widely used for management of many upper airway diseases because of their ability to effectively deliver local relief of inflammation.

CASE REPORT

This paper presents the case of a 51-year-old man with human immunodeficiency virus treated with ritonavir who was started on fluticasone intranasal spray for presumed chronic rhinosinusitis. Months after starting this therapy, he developed symptoms of Cushing's syndrome and avascular necrosis of the shoulder due to the pharmacological interactions between fluticasone and ritonavir.

CONCLUSION

Although intranasal corticosteroids are deemed a low-risk route of drug administration, clinicians need to be vigilant in appropriately prescribing corticosteroids in the setting of drug potentiators, particularly in these high-risk patients. Alternative corticosteroids such as beclomethasone dipropionate should be considered in such cases.

Gold nanoplasmonic particles in tunable porous silicon 3D scaffolds for ultra-low concentration detection by SERS

A composite material of plasmonic nanoparticles embedded in a scaffold of nano-porous silicon offers unmatched capabilities for use as a SERS substrate. The marriage of these components presents an exclusive combination of tightly focused amplification of Localised Surface Plasmon (LSP) fields inside the material with an extremely high surface-to-volume ratio. This provides favourable conditions for a single molecule or extremely low concentration detection by SERS. In this work the advantage of the composite is demonstrated by SERS detection of Methylene Blue at a concentration as low as a few picomolars. We systematically investigate the plasmonic properties of the material by imaging its morphology, establishing its composition and the effect on the LSP resonance optical spectra.

A Study of GP Workload and Satisfaction

Aims In this novel study in the Irish setting, we quantified the number items managed per General Practitioner (GP) consult, how each item is managed, and impact on a GP's job satisfaction. Methods Participating GPs at two surgeries completed a questionnaire - integrated into the practice management software - after each consultation that satisfied the inclusion criteria during a four-week period. Results Due to feasibility constraints, 500 of 857 (58.3%) completed questionnaires were randomly selected for our sample. GPs manage an average of 1.76 items per consultation. Older patients presented with more items. Greater number of presenting items led to less being managed on the day 71% (n=5) for 5 items vs. 95.2% (n= 246) for 1 item, longer consultation duration (mean = 14.63 minutes (4-45) and decreased GP satisfaction, mean 8/10 (2-10). Conclusion Increasing the number of items in a GP consultation has a statistically significant effect on duration of consultation, how each item is managed, and even GP satisfaction.

O43 Virtual: virtual interactive surgical skills classroom: a randomized controlled trial (protocol)

Introduction

High costs and inaccessibility are significant barriers to face-to-face basic surgical skills (BSS) training. Virtual classrooms enable the combination of computer-based learning with interactive expert instruction. They may optimise resources and increase accessibility, facilitating larger-scale training with a similar educational benefit. We aim to evaluate the efficacy of virtual BSS classroom training compared to both non-interactive video and face-to-face teaching.

Method

72 medical students will be randomly assigned to three equal intervention groups based on surgical skills experience and confidence. Interventions will be implemented following an instructional video. Group A will practice independently, Group B will receive face-to-face training, and Group C will attend a virtual classroom. Participants will be recorded placing three interrupted sutures with hand tied knots pre- and post-intervention. Objective Structured Assessment of Technical Skills (OSATS) will be blind marked by two experts.

Result

Change in confidence, time to completion and a novel granular performance score will also be measured. Each intervention’s feasibility and accessibility will be assessed. Significant improvement in OSATS within groups will be indicative of intervention quality. Difference in improvement between groups will determine the relative performance of the interventions.

Conclusion

This will be the largest randomised control trial investigating virtual BSS classroom training. It will serve as a comprehensive appraisal of the suitability of virtual classrooms as an alternative to face-to-face training. The findings will assist the development and implementation of further resource-efficient training programs during the COVID-19 pandemic and beyond.

Take-home Message

This is the first RCT assessing virtual basic surgical skill classroom training and serves as a comprehensive appraisal of the suitability of virtual classrooms as an alternative to face-to-face training. The findings will assist the development and implementation of further resource-efficient training programs during the COVID-19 pandemic and in the future.

O50 New guidelines to reduce unnecessary blood tests, delayed discharge and costs following robot assisted radical prostatectomy

Introduction

Routine postoperative blood tests (POBT) are used to evaluate the impact of surgery on pre-existing co-morbidities and to detect early complications. This practice dates back to an era of open surgery, when blood loss and complication rates were higher. We propose new guidelines to improve the specificity of POBT.

Method

The cases of 1040 consecutive patients who underwent a primary or salvage RARP at two large tertiary urology centres in the United Kingdom were retrospectively reviewed, and new guidelines were designed. The guidelines were prospectively validated in a cohort of 300 patients.

Result

Derivation Dataset 3% and 5% had intra- and post-operative Clavien-Dindo complications, respectively. 15% had clinical concerns postoperatively. 0.9% required perioperative transfusion. 78% had routine blood tests without clinical concerns, none of whom developed a complication. 98% of complications were suspected by clinical judgement. 6% of patients had a discharge delay of ≥ 1 days due to delayed or incomplete blood tests.

Validation Dataset No significant difference existed in complication, clinical concern or transfusion rates between the derivation and validation datasets. New guidelines improved sensitivity for complications from 98% to 100% and specificity from 0% to 74%. The number of blood tests requested reduced by 73% (P < 0.001). Discharge delays reduced from 6% to 0% (P = 0.008). Cost savings were £178 per patient.

Conclusion

Postoperative complications and transfusion following RARP are rare. Routine POBT without clinical indication are unnecessary and inefficient. A guideline-based approach to POBT can reduce costs and optimise discharge without compromising patient safety or care.

Take-home Message

Routine postoperative blood tests following robot assisted radical prostatectomy are often unnecessary. A guideline-based approach can reduce costs and optimise patient care.

Physical activity and moving more for health

Non-communicable diseases are a leading cause of death and levels are rising. Lifestyle changes, including physical activity, have benefits in all-cause mortality, cardiovascular and metabolic disease, respiratory conditions and cognitive and mental health. In some cancers, particularly colon, prostate and breast, physical activity improves quality of life and outcomes before, during and after treatment. Sedentary time is an independent risk factor with adverse effects in hospitalised patients. Mechanisms include anti-inflammatory effects and augmentation of physiological and neuroendocrine responses to stressors. Engaging patients is affected by barriers: for clinicians, awareness of guidelines and personal physical activity levels are important factors; for patients, barriers are influenced by life events, socioeconomic and cultural factors. Interventions to increase activity levels are effective in the short- and medium-term, including brief interventions. Face-to-face is more effective than remote advice and behavioural interventions are more effective than cognitive. There are no published guidelines for physical activity in hospitalised patients.

Severe COVID-19 Is Characterized by an Impaired Type I Interferon Response and Elevated Levels of Arginase Producing Granulocytic Myeloid Derived Suppressor Cells

COVID-19 ranges from asymptomatic in 35% of cases to severe in 20% of patients. Differences in the type and degree of inflammation appear to determine the severity of the disease. Recent reports show an increase in circulating monocytic-myeloid-derived suppressor cells (M-MDSC) in severe COVID 19 that deplete arginine but are not associated with respiratory complications. Our data shows that differences in the type, function and transcriptome of granulocytic-MDSC (G-MDSC) may in part explain the severity COVID-19, in particular the association with pulmonary complications. Large infiltrates by Arginase 1+ G-MDSC (Arg+G-MDSC), expressing NOX-1 and NOX-2 (important for production of reactive oxygen species) were found in the lungs of patients who died from COVID-19 complications. Increased circulating Arg+G-MDSC depleted arginine, which impaired T cell receptor and endothelial cell function. Transcriptomic signatures of G-MDSC from patients with different stages of COVID-19, revealed that asymptomatic patients had increased expression of pathways and genes associated with type I interferon (IFN), while patients with severe COVID-19 had increased expression of genes associated with arginase production, and granulocyte degranulation and function. These results suggest that asymptomatic patients develop a protective type I IFN response, while patients with severe COVID-19 have an increased inflammatory response that depletes arginine, impairs T cell and endothelial cell function, and causes extensive pulmonary damage. Therefore, inhibition of arginase-1 and/or replenishment of arginine may be important in preventing/treating severe COVID-19.

Atmospheric Carbon and Transport - America (ACT-America) Data Sets: Description, Management, and Delivery

The ACT-America project is a NASA Earth Venture Suborbital-2 mission designed to study the transport and fluxes of greenhouse gases. The open and freely available ACT-America data sets provide airborne in situ measurements of atmospheric carbon dioxide, methane, trace gases, aerosols, clouds, and meteorological properties, airborne remote sensing measurements of aerosol backscatter, atmospheric boundary layer height and columnar content of atmospheric carbon dioxide, tower-based measurements, and modeled atmospheric mole fractions and regional carbon fluxes of greenhouse gases over the Central and Eastern United States. We conducted 121 research flights during five campaigns in four seasons during 2016-2019 over three regions of the US (Mid-Atlantic, Midwest and South) using two NASA research aircraft (B-200 and C-130). We performed three flight patterns (fair weather, frontal crossings, and OCO-2 underflights) and collected more than 1,140 h of airborne measurements via level-leg flights in the atmospheric boundary layer, lower, and upper free troposphere and vertical profiles spanning these altitudes. We also merged various airborne in situ measurements onto a common standard sampling interval, which brings coherence to the data, creates geolocated data products, and makes it much easier for the users to perform holistic analysis of the ACT-America data products. Here, we report on detailed information of data sets collected, the workflow for data sets including storage and processing of the quality controlled and quality assured harmonized observations, and their archival and formatting for users. Finally, we provide some important information on the dissemination of data products including metadata and highlights of applications of ACT-America data sets.

Transcriptome and Functions of Granulocytic Myeloid-Derived Suppressor Cells Determine their Association with Disease Severity of COVID-19

COVID-19 ranges from asymptomatic in 35% of cases to severe in 20% of patients. Differences in the type and degree of inflammation appear to determine the severity of the disease. Recent reports show an increase in circulating monocytic-myeloid-derived suppressor cells (M-MDSC) in severe COVID 19, that deplete arginine but are not associated with respiratory complications. Our data shows that differences in the type, function and transcriptome of Granulocytic-MDSC (G-MDSC) may in part explain the severity COVID-19, in particular the association with pulmonary complications. Large infiltrates by Arginase 1 ⁺ G-MDSC (Arg ⁺ G-MDSC), expressing NOX-1 and NOX-2 (important for production of reactive oxygen species) were found in the lungs of patients who died from COVID-19 complications. Increased circulating Arg ⁺ G-MDSC depleted arginine, which impaired T cell receptor and endothelial cell function. Transcriptomic signatures of G-MDSC from patients with different stages of COVID-19, revealed that asymptomatic patients had increased expression of pathways and genes associated with type I interferon (IFN), while patients with severe COVID-19 had increased expression of genes associated with arginase production, and granulocyte degranulation and function. These results suggest that asymptomatic patients develop a protective type I IFN response, while patients with severe COVID-19 have an increased inflammatory response that depletes arginine, impairs T cell and endothelial cell function, and causes extensive pulmonary damage. Therefore, inhibition of arginase-1 and/or replenishment of arginine may be important in preventing/treating severe COVID-19.

Estimation of Patient Eye-Lens Dose During Neuro-Interventional Procedures using a Dense Neural Network (DNN)

The patient's eye-lens dose changes for each projection view during fluoroscopically-guided neuro-interventional procedures. Monte-Carlo (MC) simulation can be done to estimate lens dose but MC cannot be done in real-time to give feedback to the interventionalist. Deep learning (DL) models were investigated to estimate patient-lens dose for given exposure conditions to give real-time updates. MC simulations were done using a Zubal computational phantom to create a dataset of eye-lens dose values for training the DL models. Six geometric parameters (entrance-field size, LAO gantry angulation, patient x, y, z head position relative to the beam isocenter, and whether patient's right or left eye) were varied for the simulations. The dose for each combination of parameters was expressed as lens dose per entrance air kerma (mGy/Gy). Geometric parameter combinations associated with high-dose values were sampled more finely to generate more high-dose values for training purposes. Additionally, dose at intermediate parameter values was calculated by MC in order to validate the interpolation capabilities of DL. Data was split into training, validation and testing sets. Stacked models and median algorithms were implemented to create more robust models. Model performance was evaluated using mean absolute percentage error (MAPE). The goal for this DL model is that it be implemented into the Dose Tracking System (DTS) developed by our group. This would allow the DTS to infer the patient's eye-lens dose for real-time feedback and eliminate the need for a large database of pre-calculated values with interpolation capabilities.

Evaluating survey methods for bat roost detection in ecological impact assessment

The disturbance, damage and destruction of roosts are key drivers of bat population declines worldwide. In countries where bats are protected by law, bat roost surveys are often required to inform ecological impact assessments. Yet, evidence‐based information on survey methodology to detect bat roosts is crucially lacking, and failing to detect a roost can lead to serious errors during decision‐making processes. Here, we assess the efficacy of bat roost surveys in buildings as implemented in the UK. These consist of a daytime inspection of buildings, followed by a series of acoustic surveys at dusk/dawn if during the daytime inspection evidence of bats is found, or if the absence of bats cannot be verified. We reviewed 155 ecological consultants’ reports to (1) compare survey outcome between daytime inspection and acoustic surveys and (2) determine the minimum sampling effort required during acoustic surveys to be confident that no bats are roosting within a building. We focused on two genera of bats most frequently found in buildings in Europe – Pipistrellus (crevice roosting species with high‐intensity echolocation calls that can be easily detected by ultrasound detectors) and Plecotus (species that roost in open spaces and which emit faint echolocation calls that are difficult to detect). Daytime inspections were efficient in detecting open‐roosting species such as Plecotus species but were likely to miss the presence of crevice‐dwelling ones (here Pipistrellus species) which may lead to erroneous conclusions if no acoustic surveys are subsequently prescribed to confirm their absence. A minimum of three and four acoustic surveys are required to be 95% confident that a building does not host a roost of Pipistrellus species and Plecotus species, respectively, thus exceeding current recommendations. Overall, we demonstrated that reports submitted as part of an ecological impact assessment provide suitable data to test and improve survey methods.

Correction: Identification of Informed Consent in Patient Videos on Social Media: Prospective Study

[This corrects the article DOI: 10.2196/14081.].

Identification of Informed Consent in Patient Videos on Social Media: Prospective Study

BACKGROUND

The American Medical Association Code of Medical Ethics states that any clinical image taken for public education forms part of the patient's records. Hence, a patient's informed consent is required to collect, share, and distribute their image. Patients must be informed of the intended use of the clinical image and the intended audience as part of the informed consent.

OBJECTIVE

This paper aimed to determine whether a random selection of instructional videos containing footage of central venous catheter insertion on real patients on YouTube (Google LLC) would mention the presence of informed consent to post the video on social media.

METHODS

We performed a prospective evaluation by 2 separate researchers of the first 125 videos on YouTube with the search term "central line insertion." After duplicates were deleted and exclusion criteria applied, 41 videos of patients undergoing central line insertion were searched for reference to patient consent. In the case of videos of indeterminate consent status, the posters were contacted privately through YouTube to clarify the status of consent to both film and disseminate the video on social media. A period of 2 months was provided to respond to initial contact. Furthermore, YouTube was contacted to clarify company policy. The primary outcome was to determine if videos on YouTube were amended to include details of consent at 2 months postcontact. The secondary outcome was a response to the initial email at 2 months.

RESULTS

The researchers compiled 143 videos. Of 41 videos that contained footage of patient procedures, 41 were of indeterminate consent status and 23 contained identifiable patient footage. From the 41 posters that were contacted, 3 responded to initial contact and none amended the video to document consent status. Response from YouTube is pending.

CONCLUSIONS

There are instructional videos for clinicians on social media that contain footage of patients undergoing medical procedures and do not have any verification of informed consent. While this study investigated a small sample of available videos, the problem appears ubiquitous and should be studied more extensively.

Do images of dietitians on the Internet reflect the profession?

BACKGROUND

The image of dietitians presented on the Internet shapes public perception of the profession, which in turn may influence engagement with professionals. The aim was to describe the portrayal of the dietetic profession on the Internet and how this aligns with international professional demographics.

METHODS

In this cross-sectional observational study, images appearing in two Google image searches using the word 'dietitian' were analysed for content by two independent researchers. A coding framework was used to identify personal characteristics of professionals and others presented in the image, as well as the work setting. These were compared to demographic data of members of professional associations in Australia, the United Kingdom (UK) and the United States of America (USA).

RESULTS

The dietitian portrayed in the images (n = 339) was most often female (88%), Caucasian (72%), aged between 26-39 years (63%), pictured alone (78%), pictured with food (78%) and in a setting that could not be determined (76%). The age and gender profile presented matches the characteristics of the international workforce; however, there was an absence of images illustrating dietitians in authentic work roles.

CONCLUSIONS

The images resulting from an online search for 'dietitian' do not fully illustrate the profession. There are opportunities to create and share authentic images online that show the breadth of work roles and diversity of professionals' age, gender, cultural background and size.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

FRI0421 RATES OF PROGRESSION DIFFER BETWEEN STRUCTURAL PHENOTYPES OF KNEE OSTEOARTHRITIS: A SECONDARY ANALYSIS FROM THE FNIH COHORT

Background:

Imaging plays an important role in determining structural disease severity and potential suitability of patients recruited to disease-modifying osteoarthritis drug (DMOAD) trials. It has been suggested that there may be three main structural phenotypes in OA, i.e., inflammation, meniscus/cartilage and subchondral bone. These may progress differently and may represent distinct tissue targets for DMOAD approaches.

Objectives:

To stratify the Foundation for National Institutes of Health Osteoarthritis Biomarkers Consortium (FNIH) cohort, a well-defined subsample of the larger Osteoarthritis Initiative (OAI) study, into distinct structural phenotypes based on semiquantitative MRI assessment and to determine their risk for progression over 48 months.

Methods:

The FNIH was designed as a case-control study with knees showing either 1) radiographic and pain progression (i.e., “composite” cases), 2) radiographic progression only (“JSL”), 3) pain progression only, and 4) neither radiographic nor pain progression. MRI of both knees was performed on 3 T systems at the four OAI clinical sites. Two musculoskeletal radiologists read the baseline MRIs according to the MOAKS scoring system. Knees were stratified into subchondral bone, meniscus/cartilage and inflammatory phenotypes1. A secondary, less stringent definition for inflammatory and meniscus/cartilage phenotype was used for sensitivity analyses. The relation of each phenotype to risk of being in the JSL or composite case group compared to those not having that phenotype was determined using conditional logistic regression. Only KL2 and 3 and those without root tears were included.

Results:

485 knees were included. 362 (75%) did not have any phenotype, while 95 (20%) had the bone phenotype, 22 (5%) the cartilage/meniscus phenotype and 19 (4%) the inflammatory phenotype. The bone phenotype was associated with a higher risk of the JSL and composite outcome (OR 1.81;[95%CI 1.14,2.85] and 1.65; 95%CI [1.04,2.61]) while the inflammatory (OR 0.96 [95%CI 0.38,2.42] and 1.25; 95%CI [0.48,3.25]) and the meniscus/cartilage phenotypes were not (OR 1.30 95%CI [0.55,3.07] and 0.99; 95%CI [0.40,2,49]).

In sensitivity analyses, the bone phenotype and having two phenotypes (vs. none) were both associated with increased risk of experiencing the composite outcome (bone: OR 1.65; 95% CI 1.04, 2.61; 2 phenotypes: OR 1.87; 95% CI 1.11, 3.16.

Conclusion:

The bone phenotype was associated with increased risk of having both radiographic and pain progression together, or radiographic progression alone, whereas the inflammatory phenotype or meniscus/cartilage phenotype each individually were not associated with either outcome. Phenotypic stratification appears to provide insights into risk for structural or composite structure plus pain progression, and therefore may be useful to consider when selecting patients for inclusion in clinical trials.

References:

[1]Roemer FW, Collins J, Kwoh CK, et al. MRI-based screening for structural definition of eligibility in clinical DMOAD trials: Rapid OsteoArthritis MRI Eligibility Score (ROAMES). Osteoarthritis Cartilage 2020;28(1):71-81

Disclosure of Interests:

Frank Roemer: None declared, Jamie Collins Consultant of: Boston Imaging Core Lab (BICL), LLC., Tuhina Neogi Grant/research support from: Pfizer/Lilly, Consultant of: Pfizer/Lilly, EMD-Merck Serono, Novartis, Michel Crema: None declared, Ali Guermazi Consultant of: AventisGalapagos, Pfizer, Roche, AstraZeneca, Merck Serono, and TissuGene

Oncologic outcomes of patients with incidental prostate cancer who underwent RARC: a comparison between nerve sparing and non-nerve sparing approach

BACKGROUND

Incidental Prostate cancer (iPCa) is a relatively common finding during histopathological evaluation of radical cystectomy (RC) specimens. To reduce the high impact of RC on erectile function, several sexual-preserving techniques have been proposed. The aim of this study was to evaluate and compare the oncologic outcomes of patients with iPCa who underwent nerve spring and no-nerve sparing robot-assisted radical cystectomy (RARC).

METHODS

The clinicopathologic data of male patients who underwent RARC at our institution between 2006 and 2016 were retrospectively analysed. Patients with iPCa at definitive pathological examinations were stratified in two groups, according to the preservation of the neurovascular bundles (nerve sparing vs no nerve sparing). Significant PCa was defined as any Gleason score ≥ 3 + 4. Biochemical recurrence (BR) was defined as a sustained PSA level > 0.2 ng/mL on two or more consecutive appraisals. BR rate was assessed only in patients with incidental prostate cancer and at least 2 years of follow-up. Differences in categorical and continuous variables were analysed using the chi-squared test and the Mann-Withney U test, respectively. Biochemical recurrence curves were generated using the Kaplan-Meier method and compared with the Log-rank test.

RESULTS

Overall, 343 male patients underwent RARC for bladder cancer within the study period. Nerve-sparing surgery was performed in 143 patients (41%), of these 110 had at least 2 years of follow up after surgery. Patients who underwent nerve-sparing surgery were significantly younger (p < 0.001). Clinically significant PCa was found in 24% of patients. No significant differences regarding preoperative PSA value (p = 0.3), PCa pathological stage (p = 0.5), Gleason score (p = 0.3) and positive surgical margin rates (p = 0.3) were found between the two groups. After a median follow-up of 51 months only one patient, in the no-nerve-sparing group had developed a biochemical recurrence (p = 0.4).

CONCLUSIONS

In our series most of the iPca detected in RC specimens can be considered as insignificant with a low rate of BR (0.9%). Nerve-sparing RARC is a safe procedure which did not affect oncological outcomes of patients with iPCa.

Expert consensus on a train-the-trainer curriculum for robotic colorectal surgery

AIM

Robotic techniques are being increasingly used in colorectal surgery. There is, however, a lack of training opportunities and structured training programmes. Robotic surgery has specific problems and challenges for trainers and trainees. Ergonomics, specific skills and user-machine interfaces are different from those in traditional laparoscopic surgery. The aim of this study was to establish expert consensus on the requirements for a robotic train-the-trainer curriculum amongst robotic surgeons and trainers.

METHOD

This is a modified Delphi-type study involving 14 experts in robotic surgery teaching. A reiterating 19-item questionnaire was sent out to the same group and agreement levels analysed. A consensus of 0.8 or higher was considered to be high-level agreement.

RESULTS

Response rates were 93-100% and most items reached high levels of agreement within three rounds. Specific requirements for a robotic faculty development curriculum included maximizing dual-console teaching, theatre team training, nontechnical skills training, patient safety, user-machine interface training and telementoring.

CONCLUSION

A clear need for the development of a train-the-trainer curriculum has been identified. Further research is needed to assess feasibility, effectiveness and clinical impact of a robotic train-the-trainer curriculum.

Abstract P1-09-13: A real world evidence study of BRCA mutations and survival in HER2-negative breast cancer

Background: Limited data exist on the natural history (treated with standard of care) of metastatic breast cancer (mBC) characterized by germline breast cancer susceptibility gene mutations (gBRCAm). Real-world data examining survival for patients with gBRCAm mBC, overall and separated into gBRCA1m and gBRCA2m, compared to gBRCA wild type (wt) mBC, can help to clarify the prognostic outlook associated with the gBRCA mutation.

Methods: Adults with human epidermal growth factor receptor 2 negative (HER2-) mBC diagnosed from January 2013 – August 2017 were retrospectively selected from the Flatiron Health Oncology electronic medical record database. Patients were classified as having gBRCA1m, gBRCA2m, or gBRCAwt disease. Those who did not receive the genetic testing or who had equivocal results were classified as gBRCA unknown. Overall survival (OS) was calculated from first diagnosis of mBC, as well as from the start of first- and second-line therapy for metastatic disease. Lines of therapy included both hormonal and systemic therapies. Kaplan-Meier analyses provided median OS with 95% confidence interval (CI). Unadjusted log-rank tests compared OS between gBRCA1m and gBRCA2m, and between overall gBRCAm and gBRCAwt.

Results: Of 8,080 patients selected, mean age at first mBC diagnosis was 64 years, 98.7% were female, and 82.0% had evidence of hormone receptor positive disease. gBRCA status was known for 1,852 (22.9%) of patients, of whom 89 (4.8%) had gBRCA1m, 152 (8.2%) had gBRCA2m, and 8 (0.4%) had both gBRCA mutations. Patients with known gBRCA status were younger, with mean ages of 52 years for gBRCAm, 55 years for gBRCAwt, and 67 years for gBRCA unknown. Hormone receptor positive disease was less common among those with known gBRCA status (71.9%, 77.2%, and 83.6% for gBRCAm, gBRCAwt, and gBRCA unknown, respectively). Median (95% CI) OS from mBC diagnosis was 22 (14 - 26) months for gBRCA1m and 30 (27 - 37) months for gBRCA2m (p = 0.01), though numbers were quite small by the median timepoint. Overall gBRCAm disease was associated with median survival of 28 (25 - 32) months, compared to 32 (30 - 35) months for gBRCAwt (p = 0.07); survival was similar between groups for the first 24 months but declined thereafter in the gBRCAm group. Similar patterns were observed for OS after the start of first- and second-line therapy, although no comparisons were significant. Further analyses will present adjusted results and comparisons with outcomes for the patients with gBRCA unknown.

Conclusions: This real-world study of patients receiving care in largely community oncology clinics suggests that survival after diagnosis of mBC is reduced in patients with gBRCA1m compared to gBRCA2m disease and may be reduced in gBRCAm mBC overall. Effective treatments targeted for the gBRCAm subtypes of mBC appear to be needed.

Citation Format: Dalvi T, McLaurin K, Briceno J, Nordstrom B, Bennett J, Hettle R, Murphy B, Collins J, McCutcheon S. A real world evidence study of BRCA mutations and survival in HER2-negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-09-13.